JP2005255590A - Stilbene derivative, method for producing the same, and electrophotographic photoreceptor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stilbene derivative capable of being suitably used as a charge transport agent for an electrophotographic photoreceptor, etc., to provide a method for producing the same, and to provide the electrophotographic photoreceptor having excellent sensitivity behavior. <P>SOLUTION: This stilbene derivative is expressed by general formula (1) (A is a substituted or unsubstituted aromatic ring-containing tetravalent organic group; R<SP>1</SP>'s to R<SP>6</SP>'s, B's and C's are each H, a halogen, a 1-20C substituted or unsubstituted alkyl, a 1-20C substituted or unsubstituted halogenated alkyl or the like, provided that any two of R<SP>1</SP>'s to R<SP>6</SP>'s, B's and C's may be combined or condensed with each other to form a carbon ring structure; and m's are each an integer of 0 to 2) and has four triphenyl amine structures each containing an ethenyl residue. The electrophotographic photoreceptor contains the stilbene derivative. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a stilbene derivative, a method for producing the same, and an electrophotographic photoreceptor, and in particular, a stilbene derivative having four triphenylamine structures containing an ethenyl group at a predetermined position in the molecule and having a predetermined sensitivity, and a method for producing the same. And an electrophotographic photoreceptor containing such a stilbene derivative.

Conventionally, as an electrophotographic photosensitive member used for an image forming apparatus or the like, an organic photosensitive member made of an organic photosensitive material such as a charge transfer agent, a charge generating agent, and a binder resin (binder resin) has been used. Such an organic photoreceptor is advantageous in that it is easy to manufacture and has a wide degree of freedom in structural design because it has various options for the photoreceptor material as compared with conventional inorganic photoreceptors.
Among such organophotoreceptor materials, as a charge transfer agent having a predetermined charge mobility, a stilbene compound having four triphenylamine structures represented by the following general formula (72) and an electrophotographic photosensitive film using the same The body is also known (see, for example, Patent Document 1).

(In the general formula (72), R ^{15 to} R ³⁰ each represent an independent hydrogen atom, an alkyl group, or an aryl group which may have a substituent R, and A ^{1 to} A ⁴ are each It represents any of an aryl group which may have a substituent R, a diphenylaminophenyl group which may have a substituent R, and a carbazolyl group which may have a substituent R, and n is 0 or 1 In addition, each of the substituents R represents an independent hydrogen atom, alkyl group, alkoxy group, amino group, cyano group, nitro group, hydroxyl group, or halogen atom.
Japanese Patent Laid-Open No. 9-297412 (Claims)

  However, since the stilbene compound described in Patent Document 1 has a relatively small molecular weight and insufficient charge mobility, the sensitivity is insufficient when used as a charge transport agent in an electrophotographic photoreceptor. The problem was seen.

Therefore, the present inventors have excellent compatibility with the binder resin by symmetrically introducing a triphenylamine structure containing a plurality of ethenyl groups at a predetermined position in the molecule in the stilbene derivative, The present inventors have found the fact that sensitivity is improved over a long period of time and have completed the present invention.
That is, the object of the present invention is to solve the technical problems described above, and to provide a stilbene derivative that can be suitably used as a charge transport agent for an electrophotographic photosensitive member, a method for producing the same, and an electron having excellent sensitivity characteristics. It is to provide a photographic photoreceptor.

  According to the present invention, there is provided a stilbene derivative having four triphenylamine structures containing an ethenyl group, wherein the stilbene derivative is represented by the following general formula (1). can do.

(In the general formula (1), A is a tetravalent organic group containing a substituted or unsubstituted aromatic ring, and a plurality of R ^{1 to} R ⁶ , B and C are independently hydrogen atoms or halogen atoms. Substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted halogenated alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, 6 to 30 carbon atoms Any of substituted or unsubstituted aryl groups, substituted or unsubstituted ethenyl groups having 2 to 30 carbon atoms, substituted or unsubstituted aralkyl groups having 7 to 31 carbon atoms, or R ^{1 to} R ⁶ , B and C Two are bonded or condensed carbocyclic structures, and the repeating number m is an integer of 0 to 2.)

  In constituting the stilbene derivative of the present invention, the tetravalent organic group represented by the symbol A in the general formula (1) is preferably an organic group represented by the following formula (2).

(In the general formula (2), R ^{7 to} R ¹⁴ are each independently an hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted halogen group having 1 to 20 carbon atoms. An alkyl group, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms.)

Further, in constituting the stilbene derivative of the present invention, R ¹ , R ² , R ⁵ or R ^{6 in} the general formula (1) are each an independent hydrogen atom, or a substituted or unsubstituted group having 1 to 6 carbon atoms. An alkyl group is preferred.

In constituting the stilbene derivative of the present invention, R ³ or R ⁴ in the general formula (1) is an independent hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, or the following general formula The ethenyl group represented by (3) is preferable.

(In General Formula (3), each of D and E is an independent hydrogen atom, halogen atom, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or substituted or unsubstituted alkyl halide having 1 to 20 carbon atoms. Group, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted or unsubstituted aryl group having 6 to 30 carbon atoms, substituted or unsubstituted ethenyl group having 2 to 30 carbon atoms, or 7 to 31 carbon atoms A substituted or unsubstituted aralkyl group, or a carbocyclic structure in which any two of D and E are bonded or condensed, and the repeating number n is an integer of 0 to 2.)

  Another embodiment of the present invention is a method for producing a stilbene derivative represented by the reaction formula (1), wherein the formylated triphenylamine derivative represented by the general formula (4) and the formula (5) A stilbene derivative having four triphenylamine structures including an ethenyl group represented by the general formula (1) by reacting the tetraphosphate derivative represented by the formula with a base; It is a manufacturing method of a derivative.

(In the reaction formula (1), A is a tetravalent organic group containing a substituted or unsubstituted aromatic ring, and a plurality of R ^{1 to} R ⁶ , B and C are independent hydrogen atoms and halogen atoms, respectively. Substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted halogenated alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, 6 to 30 carbon atoms Any of substituted or unsubstituted aryl groups, substituted or unsubstituted ethenyl groups having 2 to 30 carbon atoms, substituted or unsubstituted aralkyl groups having 7 to 31 carbon atoms, or R ^{1 to} R ⁶ , B and C Two are bonded or condensed carbocyclic structures, and the repeating number m is an integer of 0 to 2.)

  Another embodiment of the present invention is an electrophotographic photosensitive member in which a photosensitive layer is provided on a conductive substrate, wherein the photosensitive layer includes an ethenyl group represented by the following general formula (1). An electrophotographic photoreceptor comprising a stilbene derivative having four amine structures.

(In the general formula (1), A is a tetravalent organic group containing a substituted or unsubstituted aromatic ring, and a plurality of R ^{1 to} R ⁶ , B and C are independently hydrogen atoms or halogen atoms. Substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted halogenated alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, 6 to 30 carbon atoms Any of substituted or unsubstituted aryl groups, substituted or unsubstituted ethenyl groups having 2 to 30 carbon atoms, substituted or unsubstituted aralkyl groups having 7 to 31 carbon atoms, or R ^{1 to} R ⁶ , B and C Two are bonded or condensed carbocyclic structures, and the repeating number m is an integer of 0 to 2.)

  In constituting the electrophotographic photoreceptor of the present invention, the photoreceptor layer is preferably a single layer type further containing a charge generating agent and an electron transporting agent.

According to the present invention, as represented by the general formula (1), the triphenylamine structure containing an ethenyl group is present in each of four symmetrical predetermined positions in the molecule, thereby being compatible with the binder resin. Can be provided, and a stilbene derivative having a large charge mobility and a predetermined sensitivity over a long period of time can be provided. That is, the stilbene derivative represented by the general formula (1) has a triphenylamine structure containing ethenyl groups at four symmetrical positions at the molecular end, so that the molecular weight is relatively large. Regardless, there is a feature that compatibility with the binder resin is improved due to steric hindrance and that the charge mobility is high.
Therefore, when such a stilbene derivative is used as a charge transfer agent (hole transfer agent) in an electrophotographic photosensitive member, it can exhibit excellent sensitivity characteristics over a long period of time and can form a film with a uniform thickness. It becomes possible and easy to manufacture.

  Further, when A in the general formula (1) has a predetermined organic group represented by the formula (2), the π-conjugated system is widened and the charge mobility is excellent. Therefore, by using it as a hole transport agent in an electrophotographic photoreceptor, an electrophotographic photoreceptor having stable sensitivity characteristics and excellent durability even when used for a long time can be provided.

In addition, according to the stilbene derivative of the present invention, R ¹ , R ² , R ⁵ or R ^{6 in} the general formula (1) is an alkyl group or the like, so that a stilbene derivative having a predetermined structure can be easily produced. Thus, such a stilbene derivative can be obtained stably.

In addition, according to the stilbene derivative of the present invention, when R ³ or R ⁴ in the general formula (1) is an alkyl group or the like, production of a stilbene derivative having a predetermined structure is facilitated. Can be obtained stably.
In addition, when R ³ or R ⁴ is an ethenyl group represented by the general formula (3), the intramolecular conjugation can be expanded, and as a result, it was used as a hole transport agent in an electrophotographic photoreceptor. In this case, stability and durability can be improved, and excellent sensitivity can be exhibited for a longer time.

  Further, according to the method for producing a stilbene derivative of the present invention, by reacting a formylated triphenylamine derivative having a predetermined structure with a tetraphosphate ester derivative having a predetermined structure in the presence of a base, the general formula (1) Can be efficiently obtained.

  In addition, according to the electrophotographic photosensitive member of the present invention, by containing the stilbene derivative having the predetermined structure represented by the general formula (1), the electrophotography having high charge mobility and maintaining the predetermined sensitivity for a long time. A photoreceptor can be provided.

  In addition, according to the electrophotographic photosensitive member of the present invention, an electrophotographic photosensitive member having a predetermined sensitivity over a long period of time can be obtained by using a single-layer type photosensitive member, although it is easy to configure and manufacture. Can do.

  Hereinafter, embodiments relating to a stilbene derivative of the present invention, a method for producing the same, and an electrophotographic photoreceptor will be specifically described with reference to the drawings as appropriate.

[First embodiment]
1st Embodiment is a stilbene derivative which has four triphenylamine structures containing an ethenyl group, Comprising: It is represented by following General formula (1), It is a stilbene derivative characterized by the above-mentioned. In addition, the content of R < ¹ > -R < ⁶ >, B, C, and m in General formula (1) is the definition already mentioned above.

  Here, as a suitable example of the stilbene derivative represented by the general formula (1), stilbene derivatives (HTM-A to F) represented by the following structural formulas (6) to (11) are shown.

Moreover, as a tetravalent organic group containing the substituted or unsubstituted aromatic ring represented by the symbol A in General formula (1), it is preferable that it is a carbocyclic structure represented by following formula (2). .
The reason for this is that the π-conjugated system spreads and the charge mobility is excellent due to the phenyl structure having such a specific structure. Therefore, when such a stilbene derivative of such an electrophotographic photoreceptor is used as a hole transport agent, An electrophotographic photoreceptor having stable sensitivity characteristics can be provided even when used repeatedly for a long time. In addition, such a carbocyclic structure is relatively easy to introduce, and a stilbene derivative having a predetermined stability can be obtained in a relatively high yield.

(In the general formula (2), R ^{7 to} R ¹⁴ are each independently an hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted halogen group having 1 to 20 carbon atoms. An alkyl group, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms.)

[Second Embodiment]
The second embodiment is a method for producing a stilbene derivative represented by the reaction formula (1), which is represented by the formylated triphenylamine derivative represented by the general formula (4) and the general formula (5). A stilbene derivative having a triphenylamine structure containing an ethenyl group represented by the general formula (1) is obtained by reacting a tetraphosphate derivative with a base in the presence of a base. It is. In the reaction formula (1), R ^{1 to} R ⁶ , B, C, and m are the same as those in the general formula (1) unless otherwise specified.

1. Synthesis of Formylated Triphenylamine Derivative Here, in describing the reaction formula (1), a method for synthesizing the formylated triphenylamine derivative represented by the general formula (4) as a raw material will be described in detail.

(1) Reaction formula The formylated triphenylamine derivative represented by the general formula (4) is obtained by the Vilsmeier method and the Witchhi (Vilsmeier method) as shown in the reaction formula (2) including the following first to fourth steps. It is preferable to synthesize using the Wittig method as follows.

(In the reaction formula (2), a plurality of R ^{1 to} R ⁶ , B and C are each independently an hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a C 1 to 20 carbon atom. Substituted or unsubstituted halogenated alkyl group, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted or unsubstituted aryl group having 6 to 30 carbon atoms, substituted or unsubstituted ethenyl having 2 to 30 carbon atoms Group, a substituted or unsubstituted aralkyl group having 7 to 31 carbon atoms, or a carbocyclic structure in which any two of R ^{1 to} R ⁶ , B and C are bonded or condensed, and the repeating number m is 0 to 2 (It is an integer.)

(1) -1 First Step In preparing the formylated triphenylamine derivative represented by the general formula (4), a triphenylamine derivative represented by the general formula (15) is prepared as the first step. Is preferred. That is, an aniline represented by the general formula (12) and an iodobenzene derivative represented by the general formulas (13) and (14) are reacted together to obtain a triphenylamine represented by the general formula (15). Create a derivative.

(1) -2 Second Step Next, as the second step, the obtained triphenylamine derivative represented by the general formula (15) is formylated by the first Vilsmeier method, and the general formula (16) It is preferred to make the formylated triphenylamine derivative represented.

(1) -3 Third Step Next, as the third step, the formylated triphenylamine derivative represented by the general formula (16) is represented by the general formula (17) using the Wittig method. It is preferable to add a phosphorus ylide derivative containing a styryl group to produce a triphenylamine derivative represented by the general formula (18).

(1) -4 Fourth Step Next, as the fourth step, the triphenylamine derivative represented by the general formula (18) obtained is formylated by the second Filsmeier method, and the general formula (4) It is preferred to make the formylated triphenylamine derivative represented.
Hereinafter, the content of the reaction formula (2) will be described in detail by dividing it into the first step to the fourth step, and a plurality of R ^{1 to} R ⁶ , B, C, and the like in the reaction formula (2) are described. m is the same as the content in the reaction formula (1).

(2) Specific reaction step (2) -1 First step In the first step, aniline represented by general formula (12) and two types of iodobenzene represented by general formulas (13) and (14) It is preferable to make a triphenylamine derivative represented by the general formula (15) by reacting with a derivative.
In preparing the triphenylamine derivative represented by the general formula (15), it is preferable to replace one hydrogen of the amino group constituting the aniline derivative represented by the general formula (12) with an acetyl group. That is, after protecting a part of the aniline derivative with an acetyl group, it is reacted with one kind of iodobenzene derivative. Next, it is preferable to remove the acetyl group of the obtained acetylated diphenylamine derivative and simultaneously add hydrogen, and further react with another iodobenzene derivative.

Here, the addition ratio of the aniline represented by the general formula (12) and the two types of iodobenzene derivatives (total amount) represented by the general formulas (13) and (14) is 1: 2 in molar ratio. A value in the range of ˜1: 4 is preferable.
The reason for this is that when the addition ratio of the aniline and the two types of iodobenzene derivatives is less than 1: 2, the amount of triphenylamine derivative that is the target product may be reduced. On the other hand, when the addition ratio of the aniline and the two types of iodobenzene derivatives exceeds 1: 4, a large amount of unreacted iodobenzene derivatives remain, making it difficult to purify the target triphenylamine derivative. This is because there may be cases.
Moreover, it is preferable to make the addition ratio of the iodobenzene derivative respectively represented by General formula (13) and General formula (14) into the value within the range of 1: 0.5-1: 2 by molar ratio. .
This is because when the addition ratio of the iodobenzene derivative represented by the general formula (13) and the iodobenzene derivative represented by the general formula (14) is less than 1: 0.5, the general formula (14) This is because the reactivity of the iodobenzene derivative represented decreases, and the amount of the target triphenylamine derivative produced may decrease. On the other hand, when the addition ratio exceeds 1: 2, a large amount of unreacted iodobenzene derivative represented by the general formula (14) remains, so that purification of the target triphenylamine derivative may be difficult. Because there is.

Further, when the aniline represented by the general formula (12) and the two types of iodobenzene derivatives represented by the general formulas (13) and (14) are reacted, the reaction temperature is usually in the range of 160 to 220 ° C. The reaction time is preferably set to a value within the range of 4 to 30 hours.
This is because, under such reaction conditions, a desired reaction can be efficiently performed using a relatively simple manufacturing facility.

(2) -2 Second Step Next, a formylated triphenylamine derivative represented by the general formula (16) is prepared from the triphenylamine derivative represented by the general formula (15) by using the Vilsmeier method. In this case, it is preferable to use a combination of the following compounds (i) and (ii) as the Vilsmeier reagent (Vilsmeier reagent).
(i) Halogenating agents such as phosphorus oxychloride, phosgene, oxalyl chloride, thionyl chloride, triphenylphosphine-bromine, hexachlorotriphosphazatriene
(ii) N, N-dimethylformamide (DMF), N-methylformanilide (MFA), N-formylmorpholine, N, N-diisopropylformamide, and in the present invention, as a Filsmeier reagent, phosphorus oxychloride, A combination with DMF that can also be used as a solvent is preferably used.
Furthermore, the Filsmeier method can be promoted by adding a catalytic amount of zinc chloride or the like.

In the preparation of the Vilsmeier reagent, the ratio of the compounds (i) and (ii) used is usually a molar ratio, preferably within a range of 1: 1 to 1:20. A value in the range of 1: 5 is more preferable.
Furthermore, regarding the usage amount of the Vilsmeier reagent, it is preferable to set the value within the range of 0.9 to 2 times the molar amount with respect to 1 mol of the triphenylamine derivative represented by the general formula (15). A value within the range of 1.1 times the molar amount is more preferable.
In addition, regarding the reaction conditions for carrying out the Filsmeier method to formylate the triphenylamine derivative represented by the general formula (15), the reaction is usually performed at a temperature of 130 ° C. or less, and the reaction time is within a range of 2 to 5 hours. It is preferable to set the value of

(2) -3 Third Step Next, by using the Witchhi method, the formylated triphenylamine derivative represented by the general formula (16) and the phosphorus ylide derivative represented by the general formula (17) are reacted, In preparing the triphenylamine derivative represented by the general formula (18), the addition ratio of the formylated triphenylamine derivative represented by the general formula (16) and the phosphorus ylide derivative represented by the general formula (17) Is preferably set to a value in the range of 1: 1 to 1: 3 in terms of molar ratio.
This is because the amount of triphenylamine derivative represented by the general formula (18) decreases when the addition ratio of the formylated triphenylamine derivative and the phosphorus ylide derivative is less than 1: 1. Because there is. On the other hand, when the ratio of addition of the formylated triphenylamine derivative and the phosphorus ylide derivative exceeds 1: 3, a large amount of unreacted phosphorus ylide derivative remains, so the triphenylamine derivative represented by the general formula (18) This is because it may be difficult to purify.
Therefore, the addition ratio of the formylated triphenylamine derivative represented by the general formula (16) and the phosphorus ylide derivative represented by the general formula (17) is within a range of 1: 1.2 to 1: 2. More preferably, the value of

Further, when the formylated triphenylamine derivative represented by the general formula (16) is reacted with the phosphorus ylide derivative represented by the general formula (17), the reaction temperature is usually a value within the range of 50 to 120 ° C. In addition, the reaction time is preferably set to a value in the range of 1 to 30 hours.
This is because, under such reaction conditions, a desired reaction can be efficiently performed using a relatively simple manufacturing facility.
Examples of the reagent used in the Witchhi method include n-butyllithium, sodium alkoxides such as sodium methoxide and sodium ethoxide, and metal hydrides such as sodium hydride and potassium hydride. The combination of is mentioned.

(2) -4 Fourth Step Next, the formylated triphenylamine derivative represented by the general formula (4) is obtained from the triphenylamine derivative represented by the general formula (18) using the second Vilsmeier method. Create
In implementing the second Filsmeier method, it is preferable to adopt the same conditions as in the first Filsmeier method.

(2) -5 Others When R ³ or R ⁴ in the general formula (4) is an ethenyl group, the hydrogen atom R ³ or R ⁴ is first formylated by the Filsmeier method, and then witch It can be prepared by reacting a phosphorus ylide derivative represented by the general formula (17) or the like by the method.

2. Synthesis of Tetraphosphate Derivative Next, a method for synthesizing the tetraphosphate derivative represented by the general formula (5) as a raw material for carrying out the reaction formula (1) will be described in detail.
The tetraphosphate derivative represented by the general formula (5) is preferably synthesized as shown in the following reaction formula (3).

(The symbol A in the reaction formula (3) is the same as the content of the general formula (1), and the specific example thereof is the same as the content of the formula (2), and has already been described above.)

Here, in synthesizing the tetraphosphate derivative represented by the general formula (5), for example, triethyl phosphite is used in a solvent-free or suitable manner with respect to the tetrachloromethyl derivative represented by the general formula (19). It is preferable to add it to a solvent and react. This is because the tetraphosphate ester derivative (5), which is one of the starting materials of the reaction formula (1), can be obtained in a high yield by reacting in this way.
Further, when such a synthesis reaction is caused, it is preferable that the proportion of triethyl phosphite used is at least 4 times the molar equivalent with respect to 1 mol of the tetrachloromethyl derivative represented by the general formula (19). It is more preferable to set the value within a range of ˜9 times molar amount.
Moreover, it is preferable to make this reaction temperature into the value within the range of 80-150 degreeC normally, and to make reaction time into the value within the range of 2 to 10 hours.

The solvent used for preparing such a tetraphosphate derivative is not particularly limited as long as it does not affect the synthesis reaction. For example, ethers such as diethyl ether, tetrahydrofuran and dioxane; methylene chloride, chloroform and dichloroethane Preferred examples include halogenated hydrocarbons such as benzene, toluene and other aromatic hydrocarbons, dimethylformamide and the like.
It is also preferable to add a predetermined amount of a tertiary amine when preparing a tetraphosphate derivative. This is because the tertiary amine removes the alkyl halide from the reaction system, so that the synthesis reaction of the trisphosphate ester derivative can be promoted. Suitable tertiary amines include, for example, one kind of triethylamine, tributylamine, pyridine, 4- (dimethylamino) pyridine, or a combination of two or more kinds.

3. Reaction condition (1) Reaction temperature and reaction time In the reaction formula (1), a formylated triphenylamine derivative represented by the general formula (4) and a tetraphosphate ester derivative represented by the formula (5) The reaction is usually preferably carried out at −10 to 30 ° C., and the reaction time is preferably set to a value within the range of 1 to 12 hours.

(2) Solvent Further, as a suitable solvent used for the reaction of the formylated triphenylamine derivative represented by the general formula (4) and the tetraphosphate derivative represented by the formula (5), the reaction includes Any substance that does not have an influence may be used, and examples thereof include ethers such as diethyl ether, tetrahydrofuran, and dioxane; halogenated hydrocarbons such as methylene chloride, chloroform, and dichloroethane; and aromatic hydrocarbons such as benzene and toluene.

(3) Base The base used in such a reaction includes sodium alkoxide such as sodium methoxide and sodium ethoxide, metal hydride such as sodium hydride and potassium hydride, or metal salt such as n-butyllithium. Are mentioned as preferred.
Here, it is preferable to make the addition amount of this base into the value within the range of 1.1-2 mol with respect to 1 mol of formylation triphenylamine derivatives.
This is because when the amount of the base added is less than 1.1 mol, the formylated triphenylamine derivative represented by the general formula (4) and the tetraphosphate ester derivative represented by the general formula (5) This is because the reactivity between and may be significantly reduced.
On the other hand, when the amount of the base added exceeds 2 mol, the reaction between the formylated triphenylamine derivative represented by the general formula (4) and the tetraphosphate ester derivative represented by the general formula (5) This is because it may be extremely difficult to control.

(4) Addition ratio In carrying out the reaction between the formylated triphenylamine derivative represented by the general formula (4) and the tetraphosphate ester derivative represented by the general formula (5), the addition ratio is A molar ratio of 4: 1 to 6: 1 is preferable.
The reason for this is that when the addition ratio of the formylated triphenylamine derivative and the tetraphosphate derivative is less than 4: 1, an intermediate is easily formed, and the formylated triphenylamine derivative and the tetraphosphoric acid This is because it may be difficult to react appropriately with the ester derivative. Further, when the addition ratio exceeds 6: 1, a large amount of unreacted formylated triphenylamine derivative remains, which may make purification difficult.
Therefore, the addition ratio of the formylated triphenylamine derivative represented by the general formula (4) and the tetraphosphate derivative represented by the general formula (5) is 4.2: 1 to 5. A value within the range of 5: 1 is preferred.

[Third embodiment]
The third embodiment is an electrophotographic photoreceptor in which a photoreceptor layer is provided on a conductive substrate, and the photoreceptor layer has a triphenylamine structure including an ethenyl group represented by the general formula (1). An electrophotographic photoreceptor containing a stilbene derivative.
Here, the electrophotographic photosensitive member mainly includes a single layer type photosensitive member and a laminated type photosensitive member, but the stilbene derivative of the present invention is applicable to any type.
However, it can be used for either positive or negative charge type photoconductors, has a simple structure and is easy to manufacture, can effectively suppress film defects when forming the photoconductor layer, and has few interfaces between layers. In view of easy improvement of optical characteristics, it is preferable to apply to a single layer type photoreceptor.

1. Single Layer Type Photoreceptor (1) Basic Configuration As shown in FIG. 1A, the single layer type photoreceptor 10 has a single photoreceptor layer 14 provided on a conductive substrate 12.
For example, the photoreceptor layer may be formed by using a stilbene derivative (hole transporting agent) represented by the general formula (1), a charge generating agent, a binder resin, and, if necessary, an electron transporting agent in a suitable solvent. It can be formed by dissolving or dispersing and applying the resulting coating solution onto a conductive substrate and drying. Such a single layer type photoreceptor is characterized in that it can be applied to either a positive or negative charge type with a single configuration, has a simple layer configuration, and is excellent in productivity.
Further, since the obtained single-layer type photoreceptor includes the stilbene derivative represented by the general formula (1), the residual potential is lowered and the sensor has a predetermined sensitivity. .
Furthermore, when an electron transport agent is included in the photoreceptor layer of a single-layer type photoreceptor, electrons are efficiently exchanged between the charge generator and the hole transport agent, and the sensitivity and the like are more stable. The tendency to do is seen.

(2) Charge generator (2) -1 type As the charge generator used in the electrophotographic photoreceptor of the present invention, metal-free phthalocyanine (τ type or X type), titanyl phthalocyanine (α type or Y type), It is preferable to include at least one compound selected from the group consisting of hydroxygallium phthalocyanine (type V) and chlorogallium phthalocyanine (type II).
The reason for this is to provide an electrophotographic photosensitive member with more excellent sensitivity characteristics, electrical characteristics, stability, etc. when a hole transporting agent and an electron transporting agent are used in combination by specifying the type of charge generating agent. It is because it can do.

(2) -2 Specific Examples Among these charge generators, it is more preferable to use phthalocyanine pigments (CGM-A to CGM-D) represented by the following formulas (20) to (23). preferable.

  Moreover, it is also preferable to use a conventionally known charge generating agent alone or in combination. Such charge generators include phthalocyanine pigments such as oxo titanyl phthalocyanine, perylene pigments, bisazo pigments, diketopyrrolopyrrole pigments, metal-free naphthalocyanine pigments, metal naphthalocyanine pigments, squaraine pigments, trisazo pigments, indigo Organic photoconductors such as pigments, azulenium pigments, cyanine pigments, pyrylium pigments, ansanthrone pigments, triphenylmethane pigments, selenium pigments, toluidine pigments, pyrazoline pigments, quinacridone pigments, selenium, selenium-tellurium, selenium- One kind of inorganic photoconductive agent such as arsenic, cadmium sulfide, and amorphous silicon, or a mixture of two or more kinds may be used.

Among the charge generating agents described above, in particular, when used in a digital optical image forming apparatus such as a laser beam printer or a facsimile provided with a light source such as a semiconductor laser, a photosensitive material having sensitivity in a wavelength region of 700 nm or more. Therefore, it is preferable that at least one of metal-free phthalocyanine, titanyl phthalocyanine, hydroxygallium phthalocyanine, and chlorogallium phthalocyanine is contained.
On the other hand, when used in an image forming apparatus of an analog optical system such as an electrostatic copying machine equipped with a white light source such as a halogen lamp, a photoreceptor having sensitivity in the visible region is required. Pigments and bisazo pigments are preferably used.

Moreover, when using the compound (CGM-B) represented by the formula (21) described above among the charge generating agents used in the present invention, a dispersion aid represented by the following formula (24) (for example, C. IPigment Orange 16) may be added.
This is because the charge generating agent (CGM-B) and the dispersion auxiliary agent (C. IPigment Orange 16) are used together to improve the dispersibility of CGM-B in the coating solution, and the coating solution pot This is because the life can be lengthened.
In addition, when using the dispersion | distribution adjuvant represented by Formula (24), it is preferable to make the addition amount into the value within the range of 30-200 weight part with respect to 100 weight part of all the electric charge generating agents.
The reason for this is that when the amount of the dispersion aid added is less than 30 parts by weight, dispersibility in the coating solution of CGM-B becomes insufficient, and an appropriate film as a photoreceptor cannot be produced. is there. On the other hand, when the dispersion aid exceeds 200 parts by weight, the effect of increasing the quantum yield of the charge generating agent becomes insufficient, and the sensitivity characteristics, electrical characteristics, stability, etc. of the electrophotographic photoreceptor can be improved. It is because it becomes impossible.

(3) Hole transport agent In the electrophotographic photoreceptor of the present invention, it is also preferable to incorporate other conventionally known hole transport agents into the photoreceptor layer together with the stilbene derivative of the present invention which is a hole transport agent.
Examples of such a hole transport agent include various compounds having high hole transport ability, for example, compounds represented by the following general structural formulas (25) to (37) (HTM-1 to HTM-13). .

Wherein R ^h1 , R ^h2 , R ^h3 , R ^h4 , R ^h5 and R ^h6 are independent of each other, and are a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or an alkoxy group. Represents a substituted or unsubstituted aryl group having 6 to 40 carbon atoms, a and b represent the same or different integers of 0 to 4, and c, d, e and f are the same or different. Represents an integer of 0 to 5. However, when a, b, c, d, e or f is 2 or more, each R ^h1 , R ^h2 , R ^h3 , R ^h4 , R ^h5 and R ^h6 are different. May be.)

(Wherein R ^h7 , R ^h8 , R ^h9 , R ^h10 and R ^h11 are independent of each other, and are a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, a substituted or An unsubstituted aryl group having 6 to 40 carbon atoms, g, h, i and j are the same or different integers of 0 to 5 and k is an integer of 0 to 4. When g, h, i, j or k is 2 or more, each R ^h7 , R ^h8 , R ^h9 , R ^h10 and R ^h11 may be different.)

^{(Wherein, R h12, R h13, R} h14 and R ^h15 are independent of each other, substituted or unsubstituted alkyl or alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted C 6 to 40 carbon ^{Represents an} aryl group, and R ^h16 represents a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 40 carbon atoms. M, n, o and p represent the same or different integers of 0 to 5, and q represents an integer of 0 to 6, provided that m, n, o, p or q is 2 or more. when each ^{R h12, R h13, R h14} , R h15 and R ^h16 may be different.)

( ^Wherein R ^h17 , R ^h18 , R ^h19 and R ^h20 are independent of each other, and are a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted group, An aryl group having 6 to 40 carbon atoms, wherein r, s, t and u are the same or different and represent an integer of 0 to 5, provided that r, s, t or u is 2 or more. , Each R ^h17 , R ^h18 , R ^h19 and R ^h20 may be different.)

(In the formula, R ^h21 and R ^h22 are independent of each other and represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms or an alkoxy group. R ^h23 , R ^h24 , R ^h25 and R ^h26 are independent of each other. And represents a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 40 carbon atoms.)

(In the formula, R ^h27 , R ^h28 and R ^h29 are independent of each other and represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms or an alkoxy group.)

(In the formula, R ^h30 , R ^h31 , R ^h32 and R ^h33 are independent of each other and represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms or an alkoxy group.)

(In the formula, R ^h34 , R ^h35 , R ^h36 , R ^h37 and R ^h38 are independent of each other and represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms or an alkoxy group.)

(In the formula, R ^h39 represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, R ^h40 , R ^h41 and R ^h42 are independent of each other; a hydrogen atom, a halogen atom, an alkyl group having 1 to 20 carbon atoms; Or an alkoxy group.)

(Wherein, R ^h43, R ^h44 and R ^h45 are independent of each other, represent a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group having 1 to 20 carbon atoms.)

(In the formula, R ^h46 and R ^h47 are independent of each other, and are a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted carbon atom having 6 to 6 carbon atoms. 40 aryl groups are shown.)

(In the formula, R ^h50 , R ^h51 , R ^h52 , R ^h53 , R ^h54 and R ^h5 are independent of each other, and are a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or an alkoxy group. Or a substituted or unsubstituted aryl group having 6 to 40 carbon atoms, α represents an integer of 1 to 10, and v, w, x, y, z and β may be the same or different. Represents an integer of 0 to 2, provided that when v, w, x, y, z or β is 2, each R ^h50 , R ^h51 , R ^h52 , R ^h53 , R ^h54 and R ^h55 may be different. .)

(In the formula, R ^h56 , R ^h57 , R ^h58 and R ^h59 are independent of each other, and represent a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, and Φ is It is a group represented by any one of the formula (38).)

  Further, in the present invention, together with the above-exemplified hole transport agents HTM-1 to HTM-13, etc., a conventionally known hole transport material, 2,5-di (4-methylaminophenyl) -1,3,4 Oxadiazole compounds such as oxadiazole, styryl compounds such as 9- (4-diethylaminostyryl) anthracene, carbazole compounds such as polyvinylcarbazole, organic polysilane compounds, 1-phenyl-3- (p-dimethylamino) Pyrazoline compounds such as phenyl) pyrazoline, hydrazone compounds, triphenylamine compounds, indole compounds, oxazole compounds, isoxazole compounds, thiazole compounds, thiadiazole compounds, imidazole compounds, pyrazole compounds, triazole compounds Nitrogen-containing cyclic compounds such as compounds, Singly or in combinations of two or more such engagement polycyclic compounds.

(4) Electron Transfer Agent (4) Electron Transfer Agent As the electron transfer agent used in the present invention, a compound containing a quinone derivative is preferable. This is because, by using a specific compound as an electron transport agent, the electron acceptability is excellent and the compatibility with the charge generating agent is excellent. This is because it is possible to provide an electrophotographic photoreceptor excellent in the above.

  Specific examples of these electron transfer agents include compounds (ETM-A to ETM-C) represented by the following formulas (39) to (41).

  In addition, as the electron transport agent used in the present invention, it is also preferable to include other conventionally known electron transport agents in the photosensitive layer. Examples of such an electron transport agent include various compounds having high electron transport ability, for example, compounds represented by the following general structural formulas (42) to (58) (ETM-1 to ETM-17).

(Wherein R ^e1 , R ^e2 , R ^e3 , R ^e4 and R ^e5 are independent of each other, and are a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, substituted or An unsubstituted aryl group having 6 to 40 carbon atoms or an aralkyl group, or a substituted or unsubstituted phenoxy group.

(In the formula, R ^e6 is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, R ^e7 is a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted carbon group having 6 to 6 carbon atoms. 40 represents an aryl group or an aralkyl group, a halogen atom, or a halogenated alkyl group, and γ represents an integer of 0 to 5. However, when γ is 2 or more, each R ^e7 may be different from each other. )

(In the formula, R ^e8 and R ^e9 are independent of each other, and each represents a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, δ represents an integer of 1 to 4, and ε represents Represents an integer of 0 to 4. However, when δ and ε are 2 or more, each R ^e8 and R ^e9 may be different.

( ^Wherein R ^e10 represents a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group or aralkyl group having 6 to 40 carbon atoms, a halogenated alkyl group, or a halogen atom. Ζ represents an integer of 0 to 4, and η represents an integer of 0 to 5. However, when η is 2 or more, each R ^e10 may be different.)

(In the formula, R ^e11 represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and σ represents an integer of 1 to 4. However, when σ is 2 or more, each R ^e11 may be different. good.)

( ^Wherein R ^e12 and R ^e13 are independent of each other, a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted carbon group having 6 to 40 carbon atoms) An aryl group, an aralkyloxycarbonyl group, a hydroxyl group, a nitro group, or a cyano group, and X represents an oxygen atom, = N-CN group, or = C (CN) ₂ group.

( ^Wherein R ^e14 represents a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 40 carbon atoms, and R ^e15 represents a halogen ^atom. An atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 40 carbon atoms, an alkoxycarbonyl group, an N-alkylcarbamoyl group, a cyano group, or a nitro group is represented. ^Represents an integer of 0 to 3. However, when λ is 2 or more, each ^{Re 15} may be different from each other.

(In the formula, θ represents an integer of 1 to 2)

( ^Wherein R ^e16 and R ^e17 are independent of each other, and each represents a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a cyano group, a nitro group, or an alkoxycarbonyl group. ξ represents an integer of 0 to 3. However, when ν or ξ is 2 or more, each R ^e16 and R ^e17 may be different from each other.

(In the formula, R ^e18 and R ^e19 are independent of each other, and represent a substituted or unsubstituted aryl group having 6 to 40 carbon atoms, a condensed polycyclic group or a heterocyclic group, and these groups represent a substituent. You may have.)

( ^Wherein R ^e20 represents an amino group, a dialkylamino group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms or an alkoxy group, or a substituted or unsubstituted aryl group having 6 to 40 carbon atoms, and π represents ^Represents an integer of 1 to 2. However, when π is 2, each ^{Re 20} may be different from each other.

(In the formula, R ^e21 represents a hydrogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group or aralkyl group having 6 to 40 carbon atoms.)

( ^Wherein R ^e22 represents a halogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group or aralkyl group having 6 to 40 carbon atoms, an alkoxycarbonyl group, N -Represents an alkylcarbamoyl group, a cyano group, or a nitro group, and μ represents an integer of 0 to 3. However, when μ is 2 or more, each ^{Re 22} may be different from each other.

(Wherein, R ^e23 represents a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group having 6 to 40 carbon atoms having 1 to 20 carbon atoms, R ^e24 represents a substituted or unsubstituted C 1 -C 20 alkyl group or a substituted or unsubstituted aryl group having 6 to 40 carbon atoms or a group represented by -O-R ^e24,. R ^e24 in the above groups, the above-described substituted or unsubstituted carbon Represents an alkyl group having 1 to 20 carbon atoms or a substituted or unsubstituted aryl group having 6 to 40 carbon atoms.)

(In the formula, R ^e25 , R ^e26 , R ^e27 , R ^e28 , R ^e29 , R ^e30 and R ^e31 are independent of each other, and are substituted or unsubstituted alkyl or alkoxy groups having 1 to 20 carbon atoms, substituted or An unsubstituted aryl group having 6 to 40 carbon atoms or an aralkyl group, a halogen atom, or a halogenated alkyl group, and χ and φ are the same or different integers of 0 to 4.

( ^Wherein R ^e32 and R ^e33 are independent of each other, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 40 carbon atoms, a halogen atom, Or a halogenated alkyl group, wherein τ and Ψ are the same or different and represent an integer of 0 to 4.)

(In the formula, R ^e34 , R ^e35 , R ^e36 and R ^e37 are independent of each other, and are a hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group or alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted group. An aryl group, an aralkyl group, a cycloalkyl group or an amino group having 6 to 40 carbon atoms, provided that at least two of R ^e34 , R ^e35 , R ^e36 and R ^e37 are the same group which is not a hydrogen atom; )

  In addition to the above examples, in the present invention, conventionally known electron transport materials, for example, benzoquinone compounds, malononitrile, thiopyran compounds, tetracyanoethylene, 2,4,8-trinitrothioxanthone, dinitrobenzene, dinitroanthracene, etc. , Dinitroacridine, nitroanthraquinone, dinitroanthraquinone, succinic anhydride, maleic anhydride, dibromomaleic anhydride, etc., alone or in combination.

(5) Binder Resin Various resins conventionally used in the photosensitive layer can be used as the binder resin for dispersing each component. For example, styrene-butadiene copolymer, styrene-acrylonitrile copolymer, styrene-maleic acid copolymer, acrylic copolymer, styrene-acrylic acid copolymer, polyethylene resin, ethylene-vinyl acetate copolymer, chlorinated polyethylene Resin, polyvinyl chloride resin, polypropylene resin, ionomer resin, vinyl chloride-vinyl acetate copolymer, polyester resin, alkyd resin, polyamide resin, polyurethane resin, polycarbonate resin, polyarylate resin, polysulfone resin, diallyl phthalate resin, ketone resin , Polyvinyl butyral resin, polyether resin, polyester resin, etc .; silicone resin, epoxy resin, phenol resin, urea resin, melamine resin, other crosslinkable thermosetting resins; epoxy acrylate DOO, urethane - resin such as photocurable resin such as acrylate can be used.
In particular, a polycarbonate resin is a preferable binder resin because it is excellent not only in transparency and heat resistance but also in mechanical properties and compatibility with a hole transport agent.

(6) Additive In addition to the above-mentioned components, the photoreceptor layer has various conventionally known additives such as an antioxidant, a radical scavenger, a singlet as long as the electrophotographic characteristics are not adversely affected. Deterioration inhibitors such as quenchers and ultraviolet absorbers, softeners, plasticizers, surface modifiers, extenders, thickeners, dispersion stabilizers, waxes, acceptors, donors, and the like can be blended. In order to improve the sensitivity of the photoreceptor layer, known sensitizers such as terphenyl, halonaphthoquinones, and acenaphthylene may be used in combination with the charge generator.

(7) Mixing ratio When the electrophotographic photosensitive member of the present invention is a single layer type photosensitive member, the charge generating agent is 0.1 to 50 parts by weight, preferably 0.5 to 100 parts by weight of the binder resin. What is necessary is just to mix | blend in the ratio of -30 weight part. In addition, the stilbene derivative (hole transport agent) represented by the general formula (1) of the present invention is blended in an amount of 20 to 500 parts by weight, preferably 30 to 200 parts by weight with respect to 100 parts by weight of the binder resin. Just do it. When the electron transport agent is contained, the ratio of the electron transport agent is 5 to 100 parts by weight, preferably 10 to 80 parts by weight with respect to 100 parts by weight of the binder resin.
In addition, when the electrophotographic photoreceptor of the present invention is a laminated photoreceptor, the charge generator and the binder resin constituting the charge generation layer can be used in various ratios, but the binder resin 100 can be used. It is appropriate to mix the charge generating agent in an amount of 5 to 1,000 parts by weight, preferably 30 to 500 parts by weight with respect to parts by weight. Furthermore, when the hole transport agent is contained in the charge generation layer, the ratio of the hole transport agent is 10 to 500 parts by weight, preferably 50 to 200 parts by weight with respect to 100 parts by weight of the binder resin. It is.

  The hole transport agent constituting the charge transport layer and the binder resin can be used in various proportions within a range that does not inhibit charge transport and a range that does not crystallize. 10 to 500 parts by weight, preferably 25, of the stilbene derivative (hole transport agent) represented by the general formula (1) of the present invention with respect to 100 parts by weight of the binder resin so that the charges can be easily transported. It is appropriate to blend at a ratio of ~ 200 resin. When the charge transport layer contains an electron transport agent, the ratio of the electron transport agent is 5 to 200 parts by weight, preferably 10 to 100 parts by weight, based on 100 parts by weight of the binder resin.

(8) Structure The thickness of the photoreceptor layer in the single-layer photoreceptor is 5 to 100 μm, preferably 10 to 50 μm. As the conductive substrate on which such a photoreceptor layer is formed, various conductive materials can be used, for example, iron, aluminum, copper, tin, platinum, silver, vanadium, molybdenum, chromium. , Cadmium, titanium, nickel, palladium, indium, stainless steel, brass and the like, plastic materials on which the above metal is deposited or laminated, glass covered with aluminum iodide, tin oxide, indium oxide, etc. .

  The shape of the conductive substrate may be any of a sheet shape and a drum shape according to the structure of the image forming apparatus to be used. The substrate itself has conductivity or the surface of the substrate has conductivity. If you do. The conductive substrate preferably has sufficient mechanical strength when used. When the photoreceptor layer is formed by a coating method, the charge generator, charge transport agent, binder resin and the like exemplified above are combined with an appropriate solvent, and a known method such as a roll mill, a ball mill, an attritor, a paint shaker, A dispersion liquid may be prepared by dispersing and mixing using a sonic disperser or the like, and this may be applied and dried by a known means.

  Further, regarding the configuration of the single-layer type photoreceptor 10, as shown in FIG. 1B, a barrier layer 16 is formed between the conductive substrate 12 and the photoreceptor layer 14 within a range that does not impair the characteristics of the photoreceptor. May be. Further, as shown in FIG. 1C, a protective layer 18 may be formed on the surface of the photoreceptor layer 14.

(9) Production method Various organic solvents can be used as a solvent for preparing the dispersion. For example, alcohols such as methanol, ethanol, isopropanol and butanol; aliphatic systems such as n-hexane, octane and cyclohexane Hydrocarbons: aromatic hydrocarbons such as benzene, toluene, xylene, halogenated hydrocarbons such as dichloromethane, dichloroethane, chloroform, carbon tetrachloride, chlorobenzene; ethers such as dimethyl ether, diethyl ether, tetrahydrofuran, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether Ketones such as acetone, methyl ethyl ketone and cyclohexanone; esters such as ethyl acetate and methyl acetate; dimethylformaldehyde, dimethylformamide, dimethylsulfo Sid and the like. These solvents are used alone or in admixture of two or more.
Further, a surfactant, a leveling agent, or the like may be used in order to improve the dispersibility of the charge transport agent or charge generator and the smoothness of the surface of the photoreceptor layer.

2. Multilayer Photoreceptor As shown in FIG. 2A, the multilayer photoreceptor 20 is formed by forming a charge generation layer 24 containing a charge generation agent on a conductive substrate 12 by means of vapor deposition or coating, Next, a coating liquid containing at least one stilbene derivative (hole transporting agent) represented by the general formula (1) and a binder resin is applied onto the charge generation layer 24 and dried to charge transfer layer. It is made by forming 22.
In contrast to the above structure, as shown in FIG. 2B, the charge transport layer 22 may be formed on the conductive substrate 12, and the charge generation layer 24 may be formed thereon.
However, since the charge generation layer 24 is much thinner than the charge transport layer 22, for protection, the charge transport layer 22 is formed on the charge generation layer 24 as shown in FIG. It is more preferable to form
The charge generating agent, hole transporting agent, electron transporting agent, binder and the like can be the same as those of the single layer type photoreceptor.

In the case of a laminated type photoconductor, either positive or negative charge type is selected depending on the order of formation of the charge generation layer and the charge transport layer and the type of charge transport agent used in the charge transport layer. For example, as described above, when a charge generation layer is formed on a conductive substrate and a charge transport layer is formed thereon, a hole such as the stilbene derivative of the present invention is used as a charge transport agent in the charge transport layer. When a transport agent is used, the photoreceptor is a negatively charged type. In this case, the charge generation layer may contain an electron transport agent.
When used in an image forming apparatus, the multilayer electrophotographic photosensitive member of the present invention is characterized in that the residual potential of the photosensitive member is reduced and that it has a predetermined sensitivity.
The thickness of the photoreceptor layer in the multilayer photoreceptor is about 0.01 to 5 μm, preferably about 0.1 to 3 μm for the charge generation layer, and 2 to 100 μm, preferably 5 to 50 μm for the charge transport layer. Degree.

[Example 1]
(1) Synthesis of a stilbene derivative having four triphenylamine structures containing an ethenyl group (1) -1 Synthesis of a tetraphosphate ester derivative The synthesis of a tetraphosphate ester derivative represented by formula (60) is represented by the following reaction formula ( Synthesized according to 4). That is, after adding 23.1 g (0.085 mol) of 1,2,4,5-tetra (chloromethyl) benzene represented by the formula (59) into a 500 ml flask, the phosphorous acid triethyl ester was added. 84.7 g (0.51 mol) was added, and the mixture was refluxed at 160 ° C. for 5 hours. Next, a white precipitate was obtained by cooling to room temperature, and the white precipitate obtained using hexane was washed and then vacuum-dried to obtain 36.7 g of a trisphosphate ester derivative (yield 63). .6%).

(1) -2 Preparation of triphenylamine derivative The triphenylamine derivative represented by the formula (63) was synthesized according to the following reaction formula (5).
That is, 152.0 g (1.10 mol) of anhydrous potassium carbonate and 9.5 g (0.15 mol) of anhydrous copper carbonate were added into a two-necked flask having a volume of 500 ml, heated for 2 hours, and stirred until uniform. . Next, after cooling to room temperature, 67.6 g (0.5 mol) of the aniline compound represented by the following formula (61) and 305.9 g (1.5 mol) of iodobenzene represented by the formula (62) were added. Then, it was reheated to 220 ° C. and reacted for 2.5 hours. Then, after cooling to room temperature, 100 ml of toluene was added and filtered. The obtained residue was dissolved in toluene and dried using activated clay. Thereafter, the residue was dissolved in toluene, and methanol was further added for crystallization. Thereafter, the residue was dissolved again with toluene, and methanol was further added to cause crystallization. The obtained crystals were separated by filtration and dried. Thereafter, the obtained crystal was purified using silica gel column chromatography (developing solvent: chloroform / hexane solvent) to obtain 79.3 g of a triphenylamine derivative represented by the formula (63) (yield 55.2). %).

(1) -2 Preparation of formylated triphenylamine derivative Subsequently, a formylated triphenylamine derivative represented by the formula (64) was synthesized according to the following reaction formula (6).
That is, in a 500 ml flask, 60 g (0.21 mol) of a triphenylamine derivative represented by the formula (63), 450 ml of dimethylformamide (DMF), 41.8 g (0.27 mol) of oxychlorophosphoric acid, And stirred at 85 ° C. or higher for 3 hours. After the reaction, the reaction solution was dropped into 600 ml of ion-exchanged water, and the precipitated solid was filtered off. The obtained solid was stirred and washed with ion exchange water. Thereafter, the solid was dissolved in toluene, and the organic layer was washed 5 times with ion-exchanged water. Then, anhydrous sodium sulfate and activated clay were added to the obtained organic layer, followed by drying and adsorption treatment. Thereafter, toluene was distilled off under reduced pressure, and the residue was dissolved in 200 ml of toluene and crystallized from methanol to obtain 51.4 g of a formylated triphenylamine derivative represented by the formula (64) (yield 77.6). %).

(1) -3 Synthesis of phosphorus ylide Subsequently, the synthesis of phosphorus ylide represented by the formula (66) was carried out according to the following reaction formula (7).
That is, 150 g (0.61 mol) of α-bromodiphenylmethane represented by the formula (65) and 121 g (0.72 mol) of triethanol phosphoric acid were added, heated at 210 ° C., and stirred for 1 hour. Then, after cooling to room temperature, purification was performed by vacuum distillation. The obtained residue was purified using silica gel column chromatography (developing solvent: ethyl acetate solvent) to obtain 168.4 g of phosphorus ylide represented by the formula (66) (yield 90.7%).

(1) -4 Triphenylamine Derivative Next, a triphenylamine derivative represented by the following formula (67) was synthesized according to the following reaction formula (8).
That is, after adding 25 g (0.082 mol) of phosphorus ylide represented by the formula (66) in a 1000 ml four-necked flask, argon gas replacement was performed, and further 100 ml of THF was accommodated and reacted at 5 ° C. or lower. It was. Thereafter, 51.2 ml of n-BuLi (1.6M in hexane solution) was added dropwise, and the mixture was stirred at 7 ° C. or lower for 30 minutes. Furthermore, what melt | dissolved 18 g (0.057 mol) of the formylation triphenylamine derivative represented by Formula (64) in 45 ml of THF was dripped, and it stirred for 30 minutes at 6 degrees C or less. This reaction solution was added to 500 ml of ion-exchanged water and extracted with toluene. Further, the organic layer was washed 5 times with ion-exchanged water, and then the organic layer was dried and adsorbed with anhydrous magnesium sulfate and activated clay. Thereafter, the organic solvent was distilled off, left at room temperature for 2 days, the precipitated solid was filtered off using petroleum ether, and the obtained solid was dried under reduced pressure. The obtained solid was purified by column chromatography (developing solvent: chloroform / hexane solvent) to obtain 21.4 g of a triphenylamine derivative represented by the formula (67) (yield: 80.6%). ).

(1) -5 Preparation of Formylated Triphenylamine Derivative Next, a formylated triphenylamine derivative represented by the following formula (68) was synthesized according to the following reaction formula (9).
That is, in a 500 ml flask, 20 g (0.043 mol) of the triphenylamine derivative represented by the formula (67), 300 ml of dimethylformamide (DMF), 8.6 g (0.06 mol) of oxychlorophosphoric acid, And stirred at 95 ° C. for 3 hours. Thereafter, the reaction solution was poured into 500 ml of ion-exchanged water, and the precipitated crystals were separated by filtration. The obtained solid was stirred and washed twice with ion-exchanged water. Furthermore, the obtained crystal | crystallization was dissolved in toluene, and the organic layer was wash | cleaned 5 times using ion-exchange water. Further, anhydrous magnesium sulfate and activated clay were added to the organic layer, and after drying and adsorption treatment, the solvent was distilled off under reduced pressure. The obtained residue was purified by silica gel column chromatography (developing solvent: chloroform solvent) to obtain 17.8 g of a formylated triphenylamine derivative represented by the formula (68) (yield 84.0%).

(1) -7 Synthesis of Stilbene Derivative Next, a stilbene derivative represented by the formula (7) was synthesized according to the following reaction formula (10).
That is, in a 500 ml two-necked flask, 2.23 g (0.0033 mol) of the tetraphosphate derivative represented by the formula (60) obtained in (1) -1 was added and purged with argon, followed by 50 ml of THF. And 2.28 g (0.118 mol) of NaOMe / 30 ml of THF were accommodated and stirred for 30 minutes. Next, 6.52 g (0.0132 mol) of the formylated triphenylamine derivative represented by the above formula (68) was dissolved in the container, and then stirred at room temperature for about 12 hours. Next, the reaction solution was poured into 500 ml of ion-exchanged water, and the aqueous layer was changed from neutral to weakly acidic with dilute hydrochloric acid. Furthermore, toluene extraction was performed and the organic layer was washed 5 times with ion exchange water. Thereafter, the organic layer was dried over anhydrous magnesium sulfate, and the solvent was distilled off. The obtained residue was purified by silica gel chromatography (developing solvent: chloroform / hexane) to obtain 4.88 g of a stilbene derivative represented by the formula (7) (yield 76.5%).

(2) Evaluation Using the obtained stilbene derivative as a hole transport agent, a single layer type electrophotographic photosensitive member was prepared, and the initial sensitivity and the residual potential were measured. That is, as a hole transport agent, 60 parts by weight of a stilbene derivative (HTM-A) represented by the formula (6) and an X-type metal-free phthalocyanine (CGM-) represented by the formula (20) as a charge generator. 5 parts by weight of A) and 100 parts by weight of a polycarbonate resin (Resin-A) represented by the following formula (69) as a binder resin were added to 800 parts by weight of tetrahydrofuran as a solvent. Subsequently, it was mixed and dispersed for 50 hours using a ball mill to prepare a coating solution for a single-layer type photoreceptor layer. The obtained coating solution is applied onto a conductive substrate (aluminum tube) by a dip coating method, dried with hot air at 100 ° C. for 30 minutes, and a single layer type electrophotographic film having a thickness of 25 μm. A photoreceptor was obtained.
The chargeability and sensitivity characteristics of the obtained electrophotographic photosensitive member were measured. That is, using a drum sensitivity tester (manufactured by GENTEC), the potential was measured in a state of being charged to 700 V to obtain an initial charging potential (Vo). Next, the surface of the photoreceptor was irradiated with monochromatic light (half-value width: 20 nm, light amount: 1.5 μJ / cm ² ) having a wavelength of 780 nm extracted from the light of the halogen lamp using a hand pulse filter. After irradiation, the time required for the surface potential to be reduced to _1/2 was measured, and the half-exposure amount (E _1/2 ) as an index of sensitivity characteristics was measured. Further, the potential after 330 msec from the start of irradiation was measured and set as the residual potential (Vr).

[Examples 2 to 4]
In Examples 2 to 4, 20 parts by weight of each of electron transport agents (ETM-A to C) represented by the formulas (39) to (41) were added as electron transport agents to the coating liquid of Example 1. The electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1.

[Examples 5 to 8]
In Examples 5-8, the stilbene derivative (HTM-B) represented by the formula (7) was used in place of the stilbene derivative (HTM-A) used in Examples 1-4. A single-layer type photosensitive layer was prepared and evaluated in the same manner as in 1-4.

[Examples 9 to 12]
In Examples 9-12, the stilbene derivative (HTM-C) represented by the formula (8) was used in place of the stilbene derivative (HTM-A) used in Examples 1-4. A single-layer type photosensitive layer was prepared and evaluated in the same manner as in 1-4.

[Examples 13 to 16]
In Examples 13-16, the stilbene derivative (HTM-D) represented by the formula (9) was used in place of the stilbene derivative (HTM-A) used in Examples 1-4. A single-layer type photosensitive layer was prepared and evaluated in the same manner as in 1-4.

[Examples 17 to 20]
In Examples 17-20, the stilbene derivative (HTM-E) represented by the formula (10) was used instead of the stilbene derivative (HTM-A) used in Examples 1-4. A single-layer type photosensitive layer was prepared and evaluated in the same manner as in 1-4.

[Examples 21 to 24]
In Examples 21 to 24, the stilbene derivative (HTM-F) represented by the formula (11) was used in place of the stilbene derivative (HTM-A) used in Examples 1 to 4. A single-layer type photosensitive layer was prepared and evaluated in the same manner as in 1-4.

[Comparative Example 1]
In Comparative Example 1, instead of the stilbene derivative (HTM-A) used in Example 1, a triphenylamine derivative (HTM-G) represented by the formula (70) was used, and as an electron transporting agent, An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that 20 parts by weight of the electron transfer agent (ETM-A) represented by the formula (39) was added.

[Comparative Example 2]
In Comparative Example 2, instead of the stilbene derivative (HTM-A) used in Example 1, a triphenylamine derivative (HTM-H) represented by the formula (71) was used, and as an electron transporting agent, An electrophotographic photosensitive member was prepared and evaluated in the same manner as in Example 1 except that 20 parts by weight of the electron transfer agent (ETM-A) represented by the formula (39) was added.

As described above in detail, the stilbene derivative represented by the general formula (1) of the present invention has compatibility with the binder resin by symmetrically introducing an ethenyl group into four predetermined positions in the molecule. It is excellent and has high sensitivity and charge transport ability (hole transport ability) not only in the initial stage but also for a long time.
Therefore, the electrophotographic photoreceptor of the present invention is expected to contribute to speeding up and performance enhancement of various image forming apparatuses. Furthermore, since the stilbene derivative represented by the general formula (1) has a high hole transport ability, it can be used in various fields such as solar cells and electroluminescence elements.

(A)-(c) is a figure provided in order to demonstrate the basic structure and deformation | transformation structure of a single layer type photoreceptor. (A)-(b) is a figure provided in order to demonstrate the basic structure and deformation | transformation structure of a laminated type photoreceptor.

Explanation of symbols

10: single layer type photoreceptor 12: conductive substrate 14: photoreceptor layer 16: barrier layer 18: protective layer 20: laminated photoreceptor 22: charge transport layer 24: charge generation layer

Claims (7)

A stilbene derivative having four triphenylamine structures containing an ethenyl group, which is represented by the following general formula (1).

(In the general formula (1), A is a tetravalent organic group containing a substituted or unsubstituted aromatic ring, and a plurality of R ^{1 to} R ⁶ , B and C are independently hydrogen atoms or halogen atoms. Substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted halogenated alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, 6 to 30 carbon atoms Any of substituted or unsubstituted aryl groups, substituted or unsubstituted ethenyl groups having 2 to 30 carbon atoms, substituted or unsubstituted aralkyl groups having 7 to 31 carbon atoms, or R ^{1 to} R ⁶ , B and C Two are bonded or condensed carbocyclic structures, and the repeating number m is an integer of 0 to 2.) The stilbene derivative according to claim 1, wherein the tetravalent organic group represented by the symbol A in the general formula (1) is an organic group represented by the following formula (2).

(In the formula (2), R ^{7 to} R ¹⁴ are each independently an hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted halogenated group having 1 to 20 carbon atoms. An alkyl group, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms.) R ¹ , R ² , R ⁵ or R ⁶ in the general formula (1) is an independent hydrogen atom, or a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, respectively. The stilbene derivative according to 1 or 2. R ³ or R ⁴ in the general formula (1) is an independent hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, or an ethenyl group represented by the following general formula (3). The stilbene derivative according to any one of claims 1 to 3.

(In General Formula (3), each of D and E is an independent hydrogen atom, halogen atom, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, or substituted or unsubstituted alkyl halide having 1 to 20 carbon atoms. Group, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted or unsubstituted aryl group having 6 to 30 carbon atoms, substituted or unsubstituted ethenyl group having 2 to 30 carbon atoms, or 7 to 31 carbon atoms A substituted or unsubstituted aralkyl group, or a carbocyclic structure in which any two of D and E are bonded or condensed, and the repeating number n is an integer of 0 to 2.) A method for producing a stilbene derivative represented by reaction formula (1), wherein a formylated triphenylamine derivative represented by general formula (4) and a tetraphosphate ester derivative represented by formula (5) A method for producing a stilbene derivative, which is reacted in the presence to obtain a stilbene derivative having four triphenylamine structures containing an ethenyl group represented by the general formula (1).

(In the reaction formula (1), A is a tetravalent organic group containing a substituted or unsubstituted aromatic ring, and a plurality of R ^{1 to} R ⁶ , B and C are independent hydrogen atoms and halogen atoms, respectively. Substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted halogenated alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, 6 to 30 carbon atoms Any of substituted or unsubstituted aryl groups, substituted or unsubstituted ethenyl groups having 2 to 30 carbon atoms, substituted or unsubstituted aralkyl groups having 7 to 31 carbon atoms, or R ^{1 to} R ⁶ , B and C Two are bonded or condensed carbocyclic structures, and the repeating number m is an integer of 0 to 2.) An electrophotographic photoreceptor having a photoreceptor layer provided on a conductive substrate, wherein the photoreceptor layer comprises a stilbene derivative having four triphenylamine structures containing an ethenyl group represented by the following general formula (1): An electrophotographic photosensitive member characterized by containing.

(In the general formula (1), A is a tetravalent organic group containing a substituted or unsubstituted aromatic ring, and a plurality of R ^{1 to} R ⁶ , B and C are independently hydrogen atoms or halogen atoms. Substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted halogenated alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, 6 to 30 carbon atoms Any of substituted or unsubstituted aryl groups, substituted or unsubstituted ethenyl groups having 2 to 30 carbon atoms, substituted or unsubstituted aralkyl groups having 7 to 31 carbon atoms, or R ^{1 to} R ⁶ , B and C Two are bonded or condensed carbocyclic structures, and the repeating number m is an integer of 0 to 2.)   The electrophotographic photosensitive member according to claim 6, wherein the photosensitive layer is a single layer type further containing a charge generating agent and an electron transporting agent.

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